Foams such as polyurethane have been long used to insulate cabinets of consumer appliances such as refrigerators and freezers, water heaters, coolers, etc. Typically, these foams are introduced into a case structure of such a cabinet via a pour hole at or near the top of the case or a side of a case. The case structure is often made from an outer metal case and one or more inner liners made of pre-molded plastic. The foam is poured or injected in an amount taking less space than the void to be filled and then expands to fill the void within the case structure while the void is vented to let air escape during the filling and expansion. The expanded foam then hardens in place, providing a lightweight and effective insulation of the cabinet.
It can be difficult to fill a complex case structure completely and uniformly with foam. Typical foam insertion occurs from a single pour hole, from which the foam must expand to fill the case structure. In particular, newer case designs may call for more complex shapes and arrangements of parts such as ice makers and dispensers, shelving, drawers, filters, etc., within the fresh food and/or freezer compartments. Also, in some locations where conductivity is desired to be higher, the foam must be thinner, less dense, or simply absent. Accordingly, in several of such scenarios it can be an even greater challenge to fill the case structure with foam to a desired level.
Use of multiple pour holes in an attempt to better reach all locations within the case adds complexity to the fill process. As such, multiple external nozzles, foam and blowing agent supplies, connection points, and filling steps are required. Thus, attempting to fill a case using multiple pour holes undesirably multiplies costs and complexity, perhaps by a factor of the number of holes used.
Therefore, an improved foaming system and method that provide an even more reliable distribution of insulation foam and which was modifiable for various applications would be welcome.